National recovery plan for Twelve Threatened Spider-Orchid Caladenia R. Br. Taxa of Victoria and South Australia 2000 - 2004

James A. Todd
Department of Natural Resources and Environment, Victoria
Flora and Fauna Statewide Programs, March 2000

Action 7: Establish ex-situ collections of threatened Caladenia taxa with rapidly declining or critically low populations in the wild

Populations of endangered Caladenia taxa need to be established and maintained in cultivation as insurance against catastrophe and further loss in the wild, and to provide plants for introduction to additional habitat or reintroduction to known or assumed former habitat. A number of spider-orchid taxa have been successfully propagated and cultivated in the past (eg. Carr 1988; D. Tonkinson, NRE, pers. comm.) and techniques are now available that ensure a reasonable level of confidence with respect to ex-situ cultivation of threatened taxa (K. Dixon, KPBG, pers. comm.).

Caladenia species can be successfully grown from seed and maintained in cultivation, although this is not an easy task, requiring specialist equipment and expertise.

A current collaborative project between RBG, RMIT, UMILFR and NRE to look at strategies for increasing population sizes of threatened Caladenia in Victoria, is focussing on developing techniques to improve survival of deflasked Caladenia seedlings. The PhD research project is also conducting seed viability trials and attempting to isolate various mycorrhizal fungi (Ruth Raleigh, University of Melbourne, in prep.). The results of this research will be used for developing ex-situ populations of various threatened Caladenia taxa for re-introduction to the wild.

Some commercial nurseries and private growers have an excellent record in keeping Caladenia species in cultivation. NRE is overseeing the operation of the Native Orchid Growers Network (NOGN) to bring together horticultural expertise amongst the orchid growing community to assist in the cultivation of threatened orchids for recovery programs. The involvement of NOGN in the recovery effort for various threatened Caladenia taxa will be instrumental in achieving this objective.

7.1 Isolate and culture mycorrhizal fungi

Techniques are being developed by a number of different institutions for isolating and culturing mycorrhizal fungi species associated with Caladenia taxa. Kings Park Botanic Garden, Perth has been able to successfully culture the mycorrhizal fungus associated with Caladenia hastata while research has been undertaken at the University of Melbourne and Royal Botanic Gardens, Melbourne to isolate and culture the fungi associated with a number of threatened and non-threatened Caladenia taxa. Work on isolating and culturing mycorrhizal fungi associated with all threatened Caladenia taxa will continue as part of the current recovery plan.

The project will provide information to assist with management of field populations, reintroductions and will enhance propagation and cultivation outcomes. The work will require specialist expertise in mycology, particularly the identification and culture of fungi in the laboratory. The University of Melbourne, Institute of Land and Food Resources, Burnley will undertake the work for all taxa. Portland Aluminium and Kings Park Botanic Gardens, Perth will continue their fungal involvement with C. hastata.

Funding is required for years 2 and 3 of recovery inclusive to enable the purchase of laboratory consumables and to pay for a contractor to collect, culture, store and supply fungal replicates. Laboratory facilities will be donated in kind by UMILFR as part of their contribution to the recovery of threatened Caladenia taxa as will staff time for project supervision (see Action 7.2). The project will be managed under contract to NRE, which will also provide staff to assist with the collection of collars or root tips and/or the laying of fungal baits in the field as required. Senior research staff from the University of Melbourne, the National Herbarium of Victoria and the Royal Melbourne Institute of Technology will provide project supervision in kind.

C. amoena

C. audasii

C. formosa

C. fragrantissima ssp. orientalis

C. hastata

C. lowanensis

C. robinsonii

C. rosella

C. tensa

C. thysanochila

C. versicolor

C. xanthochila

Action 7.1

Responsibility

NRE - PFF/ PP, UMILFR , RBG, RMIT, EH